The present invention relates to a method of creating unique user aliases for users in a communications network, such as, for example, an MS/Exchange network.
An MS/Exchange Network comprises a collection of autonomous MS/Exchange sites, which are a collection of one or more MS/Exchange servers. MS/Exchange is a non-Internet-based email system. Its internal addressing is X400. However, directories are largely used to hide these complexities from users. When email has to leave an MS/Exchange server, via a gateway, e.g. Internet, an address mapping using a directory must take place between the internal name of the user and an alias address suitable for the gateway.
An X400 address is of the form:
Given name=Lee , Surname=Millard, ADMD=, PRMD=Exchange Organisation Name, Organisation=Exchange Site Name
whereas, for example, an Internet or SMTP (Simple Mail Transfer Protocol) alias is an email address in the form:
User @ domain, eg. Lee.Millard@uk.ibm.com
The design of MS/Exchange thus forces unique X400 user names around a worldwide organisation. Sites cannot connect unless they have a unique Exchange Organisation and Site name combination. Thus, every user will have a unique X400 alias.
In an MS/Exchange network, however, each site controls the allocation of other email aliases (e.g. Internet aliases) for users within the site. So, although an internet alias defaults to:
Firstname.Lastname@site.organisation.com (which is unique)
It can be changed by an administrator and will typically be changed as the xe2x80x9csite / internet domain aliasxe2x80x9d relationship does not often match. A worldwide company, for example, may require a common domain name for all its employees, e.g., Lee.Millard@multinational.com. This can be changed independently in each MS/Exchange Site. So, because the allocation of Internet addresses is not controlled centrally, one server may allocate the same alias for a user as another server in another site.
When MS/Exchange sites are connected together, their directories can be synchronised through replication. MS/Exchange Directory replication does not correct the problem of allocating duplicate aliases.If any aliases are duplicated, the user aliases become unusable for external traffic. There is no method of detecting the duplicates until the user attempts to use the alias for external mail. Further, because the format of the alias is determined independently by each site, no central control of the format is possible.
This is a problem within Exchange which is not fully recognised by many implementors, and which reveals itself, in particular, if an organisation utilises a single server to act as a mail gateway to either the Internet, SNADS, Lotus Notes or some other mail system where the Exchange site may set an alias independently. In such a case, external mail is sent to the gateway server, and a copy of the replicated directory local to the gateway server is used to identify the alias of the sender. The gateway server, although served by MS/Exchange directory replication, has the inherent problem of duplicate or uncontrolled alias allocation as previously described.
It is an object of the present invention to mitigate these problems.
Accordingly, the invention provides a method of creating unique user aliases for users, comprising the steps of: from a mail server in a network, exporting a user directory to the gateway server, said user directory containing a plurality of user mail address attributes dependent on a unique attribute of said user""s mail server; extracting from said directory a unique mail address attribute for each user; and from said mail address attribute, generating a unique user alias for said gateway.